A heat-medium discharge device and a heat-medium discharge method capable of discharging a heat medium from a solar heat collection device by gravity without installing a tank at a position lower than the solar heat collection device are provided. Since a heat-medium discharge device includes: a vent portion (15) which is provided at a highest position of a heat medium channel (2) of a solar heat collection device (1); an angled pipe (5) which is connected to the heat medium channel (2); a drain container (16) which is connected to a position lower than the connection portion of the heat medium channel (2) in the angled pipe (5) ; and a pump (20) which feeds the heat medium from the drain container (16) to the tank (6), the vent portion (15) is opened to introduce air during a heat medium discharge operation so that the heat medium flows through the heat medium channel (2) and the angled pipe (5) by gravity, is received in the drain container (16), and is further fed to the tank (6) by the pump (20). Accordi
